From Hackepedia
Privacy Settings
Account -> Privacy settings -> Personal information and posts
Don't leave any of these on "Everyone"
Account -> Privacy settings -> Contact information
Don't leave any of these on everyone except "Add me as a friend" and/or "Send me a message"
Account -> Privacy settings -> Friends, tags and connections
Don't leave any of these on "Everyone"
Account -> Privacy settings -> Applications and websites> Instant Personalization Pilot Program/Edit Settings
Uncheck "Allow".
Account -> Privacy settings -> Search
Change from Everyone to Friends of friends. Uncheck the allow for "Public search results"
Account -> Privacy settings -> Customize settings -> Friends can check me in to places -> Disabled
